The continuous development of communication techniques are significantly influencing people's daily life and social life, especially with the presence of various wideband access techniques. More and more people may thus enjoy the ease of their work, life and entertainment rendered by the wideband techniques. At the same time, however, wideband access techniques are also increasing the complexity of networks, and the difficulty of network maintenance. There is a need for administrators to know the actual operating conditions in the networks at any time.
According to the conventional narrowband accessing scheme, a network application model is as shown in FIG. 1. FIG. 1 is a schematic diagram showing the structure of a conventional narrowband access network according to the prior art. As shown in FIG. 1, a narrowband access equipment is located at a center office (CO) and provides twisted-pair interfaces for connecting voice terminal equipments located at the subscriber side, such as plain old telephone service (POTS). These voice terminal equipments access a public switched telephone network (PSTN) through V5/E1 interfaces provided by the narrowband access equipment located at the CO, thereby achieving a narrowband access function. Because the number of access subscribers is large, a challenge that an operator must deal with is how to reasonably plan and configure these subscribers to achieve a maximal utilization of V5/E1 resources.
In the network planning, each of network nodes is planned in view of its uplink bandwidth and the maximal number of supported subscribers, and information associated with the planning is configured in a network management central for later management. The information includes the exchanging capacity of a node in time division multiplexing (TDM), the maximal number of V5 interfaces supported by the node, the number of 2 M (i.e. E1) links provided by each V5 interface, the maximal number of POTS subscribers supported by the node and etc.
At present, in the narrowband access terminology, a service convergence ratio usually refers to a ratio between the number of slots in 2 M links provided by V5 interfaces of an access equipment, and the maximal number of POTS subscribers supported by the access equipment. By knowledge of the service convergence ratio, it is possible to acquire the utilization of resources provided by the access equipment, and then to reasonably expand the capacity of the access equipment. As shown in FIG. 1, assuming that the narrowband access equipment is able to provide ten E1 interfaces and the narrowband apparatus is planed to support up to 600 POTS subscribers, the service convergence ratio of the narrowband access equipment can be calculated as a ratio between the value obtained by multiplying the number of slots provided by each E1 interface and the number of the E1 interfaces, and the number of the POTS subscribers. For example, each E1 provides thirty-two slots, assuming that there are thirty slots available for instant service. At this time, the service convergence ratio of the narrowband access equipment is (30×10):600=1:2.
For current methods of obtaining the service convergence ratio, it is impossible to accurately acquire the service convergence ratio of each interface provided by a narrowband access equipment, because the methods determine the service convergence ratio of the access device from the maximal number of configurable V5 interfaces and the maximal number of supportable subscribers of the access equipment.
Even if the V5 interfaces are provided by the same access equipment, the number of configurable 2 M links may not always be equal for each V5 interface. Consequently, the above service convergence ratio determined for the access equipment cannot really reflect the actual service convergence ratio of each V5 interface provided by the access equipment. For example, assuming that the narrowband access equipment as shown in FIG. 1 provides ten E1 interfaces, and each of the E1 interfaces provides thirty slots for instant services; the narrowband access equipment is planned to support up to 600 POTS subscribers, and is configured with two V5 interfaces, where a V5 interface 1 is configured with one 2 M link, and a V5 interface 2 is configured with two 2 M links; 120 POTS subscribers are configured for the V5 interface 1, and 480 POTS subscribers are configured for the V5 interface 2.
The service convergence ratio of V5 interface 1 is (30×1):120=1:4, meaning that the V5 interface 1 may operate normally only if its actual service convergence ratio is equal to or greater than ¼; the service convergence ratio of the V5 interface 2 is (30×2):480=1:8, meaning that the V5 interface 2 may operate normally only if its instant service convergence ratio is equal to or greater than ⅛. In view of the overall planning for the narrowband access equipment, however, the service convergence ratio of the access equipment is (30×10):600=1 2, meaning that the narrowband access equipment can operate normally only if its instant service convergence ratio is equal to or greater than ½. It is obvious that with the current method of obtaining the service convergence ratio simply by considering the access equipment as a whole, the obtained service convergence ratio cannot reflect the real service convergence ratio of each V5 interface in the access equipment, and may depart from the real one significantly. The service convergence ratio obtained by taking the access equipment as a whole is not reliable for determining the ability of the V5 interfaces in supporting subscribers. Furthermore, the requirement on actual service convergence ratio is stricter than the two configured V5 interfaces. For example, in case the above service convergence ratio of the access equipment is used to determine the configuration of the V5 interface 1, according to the service convergence ratio of V5 interface 1=(30×1):the maximal number of supportable POTS subscribers=1:2, it is derived that the maximal number of accessing POTS subscribers through the V5 interface 1 is 90. It is obvious that the value is much less than the number 120 of POTS subscribers that the V5 interface 1 can actually support, thus causing waste of resources of the two V5 interfaces.
In addition, in the method of obtaining the service convergence ratio according to the prior art, there is no bandwidth convergence ratio provided for a broadband access network. With regard to the narrowband access network, the obtained convergence ratio may limit the ability of subscribers supported by the access equipment in simultaneous calls. As compared to the narrowband access network, there is no limit on simultaneous service provisioning for the broadband access network. However, because of the bandwidth limitation for uplink ports, it is impossible to accommodate infinite accessing subscribers. Therefore, for the broadband access network, it is necessary to know how many subscribers can be appropriately supported under uplink bandwidth condition provided by the network.
At present, although operators have carefully planned the network before construction, in the actual operating environment, they are not able to judge accurately, for example, whether it is necessary to add V5 interfaces, or add 2 M links to the configured V5 interfaces when expanding capacity to accommodate more subscribers, nor to accurately know operating conditions of the V5 interfaces.